1. Field of the Invention
The present invention generally relates to a through hole capacitor capable of improving capacitance and a method of manufacturing the same.
2. Description of Related Art
Capacitors on a circuit board are mostly surface mounted device (SMD) elements in conventional art, which are fixed on pads fixed on the circuit board.
With the increasingly complicated functions of IC, the number of pins for connecting other elements on the outside is increased, such that the wiring of the circuit board gets more and more complex, and the installation of the SMD capacitor also occupies the surface area of the IC substrate. Therefore, a circuit board with more layers is required or the area of the circuit board is required to be increased, thus increasing the manufacturing cost.
Further, in order to meet the requirements for multiple functions of electronic products, packaging ICs with different functions into a multi-functional IC module in a 3-dimensional stack is the technical trend of system in package (SiP). With the increasing layers of the stack, the conventional arrangement of SMD capacitors on the circuit board is no longer able to stabilize the voltage in multiple chip stacking.
Accordingly, a through hole capacitor structure capable of reducing the occupied surface area of the circuit board has been developed, as shown in FIG. 1. Referring to FIG. 1, a conventional through hole capacitor 10 includes two conductive layers 104 and 106 in a through hole 102 of a substrate 100 and a dielectric layer 108 between the conductive layers 104 and 106. As the capacitor does not occupy the surface area of the circuit board, it has been disclosed in many patents, for example, Taiwan Patent Publication No. 525417, U.S. Pat. Nos. 6,717,071, 6,518,670, and 6,446,317.
Although the through hole capacitor disclosed in the above patents can save the area of the circuit board, it has a low capacitance. Especially, with the increasing layers of the IC stack, some ICs may require a large transient current, such that a high-capacitance capacitor is required to stable the voltage and current of the entire element.